Safety developments in recent years for automotive vehicles and particularly passenger cars, have led to the development of so-called shoulder belts which can form part of a seat belt arrangement passing over the lap of the driver or passenger, or separate therefrom so that at least one belt or belt pass can extend diagonally across the chest and torso of the driver from one shoulder to the seat.
Such belts are generally referred to as safety belts and specifically as shoulder belts. Shoulder belts generally pass through or are provided with a guide at the side of the vehicle at which the shoulder belt is at its highest point.
In active belt systems, i.e. belt systems in which the shoulder belt automatically engages the torso of the passenger, the upper guide point of the belt is adjustable as to its height by the active belt applying system.
However, in passive shoulder belt systems, this upper guide point has been fixed. This is especially the case where the upper guide point is located on a door of the vehicle. Such systems are in common use in the United States at this time.
The fixed location of the guide point of a passive belt system, however, poses a problem because the comfort of the user frequently requires different guide points for the shoulder belt on the vehicle body and any adjustability cannot be at the expense of safety.